The Heidrun field is located in the Halten Terrace of the Mid-Norwegian Continental Shelf and is one of the first giant oil fields found on the Norwegian Sea.
Modern 3D seismic reflection data acquired over the field, as well as well data were used
to define the key structural and stratigraphic elements within the study area. The basic
geologic history of the Heidrun field is typical of most North Sea plays, and includes
Triassic rift sequences that are masked by the reactivation of bounding faults that were
active during the Jurassic rift phase. This rifting phase was followed by deposition of
marine black shales and subsequent carbonaceous shales during the Latest Jurassic to Earliest Cretaceous. The next sequence was characterized by the deposition of Paleocene-Eocene boundary tuffs, which were formed due to volcanism associated with a rifting
event that separated Norway and Greenland. Finally, an Eocene to present passive margin marine sequence is dominant over the study area that is mainly composed by glacial deposits. Traditional reservoir intervals within the Heidrun field are located within the Jurassic age inter-rift sequence. However, most recently Cretaceous-age turbidites have
been explored in the Norwegian and North Sea as possible targets with some success.
These Cretaceous turbidites are traditionally found as basin floor fan deposits within
rifted deeps along the Norwegian continental shelf and are believed to be sourced from localized erosion of Jurassic- age rifted highs. Data within our study area revealed the existence of a deep-water Cretaceous age wedge located within the downthrown hanging
wall of several smaller half-grabens formed on the Halten Terrace. Seismic attribute
extractions taken within this Cretaceous wedge show the presence of several elongate to
lobate bodies that seem to cascade over fault-bounded terraces associated with the rifted
structures. These high amplitude elongated bodies are interpreted as proximal
sedimentary conduits that are time equivalent to the Cretaceous basin floor fans located
in more distal portions of the basin to the west. Several wells penetrate the updip, tilted
half-graben hanging walls which are believed to be sourcing these turbidite systems.
These half graben fills have the potential to contain high quality Cretaceous sandstones
that might represent a potential new reservoir interval within the Heidrun field. / text
Identifer | oai:union.ndltd.org:UTEXAS/oai:repositories.lib.utexas.edu:2152/ETD-UT-2011-05-3262 |
Date | 15 July 2011 |
Creators | Ramnarine, Sarika Kala |
Source Sets | University of Texas |
Language | English |
Detected Language | English |
Type | thesis |
Format | application/pdf |
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